Oiling system for internal combustion engines



Nov. 2, 1943.

w. c. CONOVER ET AL 1 2,333,524

OILING SYSTEM FOR INTERNAL COMBUSTION ENGINES Filed Jan. 6, 1941.

INVENTORS WW/PEEN C. Co/vou se CLflkE/VCE A Joy/v.5 a/v Patented Nov. 2, 1943 OILING SYSTEM FOR INTERNAL COMBUSTION ENGINES Warren 0. Conover and Clarence L. Johnson,

Waukegan, 111.; said- Conover assignor to Outboard, Marine & Manufacturing Company, Waukegan, 111., a corporation of Delaware, and said Johnson assignor to Johnson Brothers Engineering Corp., Waukegan, 111., a corporation of Indiana Application January 6, 1941, Serial No. 373,242

7 Claims.

-'vide novel and improved means for returning to the crank case of an internal combustion engine oil which has escaped therefrom through a crank shaft or other bearing. Suction can be obtained from the crank case either by connecting the return line to the carburetor or to a small rotary valve in the shaft bearing which may have this exclusive function and no other. The present disclosure includes a connection to the carburetor manifold and also a connection through a rotary valve in the crank shaft.

From another aspect, it is the object of the invention to use for the collection of leaking oil a channel having an inner periphery which is smaller than the external peripheral diameter of the shaft along which the leakage occurs.

It isa further object of the invention to provide an engine lubricating system in which leaking oil of a two-cycle engine having more than one crank case is picked up and distributed as between the several crank cases so that each gets its proper share of the returned oil.

A further object is generally to simplify and improve the construction, arrangement and op eration for one or more of the purposes mentioned, and still other objects will be apparent from the specification.

' The drawing showsa vertical axial-section through the engine of an outboard motor, the invention being exemplified by said engine.

The particular type of engine selected as an exemplificat/ion for the invention is one havin dual carburetion with separate high speed and low speed jets. as described in C. L. Johnson Patent 2,185,506 of January 2, 1940. As used in an outboard motor structure, a conventional bracket I has a swivel bearing 2'in which the drive shaft housing 3 is rotatable for steering. The flange 4 of the drive shaft housing supports the bearing portion 5 of the dual crank case housing 6, having separate crank cases 1 and 8 in which the cranks 8 and III of the crank shaft ll rotate.

leak from crank case 1 through bearing l1 into crank case 8 and from crank case 8 through bearing l6 and downwardly along the drive shaft I8 which extends through the shaft housing 3.

In-accordance with the present invention, that portion of flange 4 which immediately underlies the bearing between the bushing l6 and the lower end of the crank shaft is provided with an oil collecting channel at 20. A series of communicating ducts ll, 22 and 23 lead from the channel upwardly through the crank case housing 6 to the low speed carburetor manifold passage 25. As explained in the Patent No. 2,185,506 aforesaid, the manifold passage 25 takes in air at 26, carburetes such air through a mixture of gasoline therewith at the nozzle 21 and delivers the carbureted air alternately into the respective crank cases I and 8 through a rotary valve mechanism comprising a port 28 in the cennected with crank Ill, moves outwardly in its The housing 6 provides an upper bearing at l5,

shaft is vertical. thereis a tendency for oil to 5 cylinder, it will, in turn, subject crank case 8 to vacuum and at that time the crank shaft passage 30 will communicate with port 28 and manifold 25 to receive its low speed charge.

. The low speed manifold is not subject to the control of any throttle valve and hence the conditions existing therein are substantially uniform at all engine speeds. In other words,'while the manifold is referred to as a low speed manifold, for the reason that it supplies all the fuel mixture required at low speeds, it nevertheless continues to supply the same amount of mixture, relatively at all engine speeds. Consequently, it is particularly desirable that the series of oil return ducts from the Pick-up channel 20 should We claim: I

1. In a two-cycle engine, the combination with a plurality of crank cases, of a crank shaft having cranks in the respective crank cases, cylinders connected with the respective crank cases, pistons connected with the respective cranks and operative in the respective cylinders whereby to subject crank cases alternately to pressure and vacuum, a bearing for said crank shaft in one 'of said crank cases, a manifold passage, rotary valve means rotatable with the crank shaft and adapted alternatively to provide communication between said passage and the respective crank cases at times of vacuum in the respective crank cases, whereby to maintain said passage substantially continuously subject to vacuum, means providing a lubricant collecting channel below said bearing, said shaft having an annular margin immediately overlapping said channel and duct means leading from said channel to said manifold passage whereby lubricant leaking through said bearing is returned with combustible mixture to the respective crank cases.

2. The combination with a vertical crank shaft having a plurality of cranks, of a crank case housing providing a plurality of crank cases and an intervening central bearing for said shaft, said crank case housing also having a lower bearing for said shaft, a carburetor manifold passage leading to said central bearing, said crank shaft having rotary valve ports adapted alternately to register with said passage in course of crank shaft rotation and to afford communication with the respective crank cases alternately, means providing an oilcollecting channel below said lower crank shaft bearing, said shaft having an annular margin at the lower end of the bearing overlapping said channel, said housing being provided with duct means leading from said channel to said manifold passage whereby lubricant collected in said channel is restored alternately to the respective crank cases.

3. The combination with an upright crank shaft, of a crank case provided with lower bearing for said shaft, a flanged housing supporting said crank case and provided with a channel immediately below and across the end of said bearing and at least a portion of said shaft, whereby the bearing surface is directly over said channel and drains therein, a carburetor manifold passage leading to said crank case, means controlling communication between, said passage and crank case and duct means leading from said channel to said passage.

4; In an internal combustion engine, the combination with an upright crank shaft provided with a lower terminal margin, of a crank case adapted to contain oil and provided with a lower bearing for said shaft to be lubricated'by said oil, a housing supporting said crank case and provided with an annular channel immediately below the end of said bearing and across said shaft margin and positioned to receive oil seepage from the crank case downwardly between the bearing and the shaft, and suction means for returning the oil from the channel back to the crank case.

5. An internal combustion engine structure including in combination, a crank shaft adapted to operate in a vertical position, a crank case adapted to contain oil and provided with a bearing in the lower wall thereof in which the lower end of the crank shaft terminates, a housing supporting said crank shaft and provided with a flange portion channelled immediately below the lower end of said crank shaft and said bearing,

said channel being of substantially annular form cylinder and piston, each compartment adapted to contain oil, said crank case being provided with a lower bearing. for said shaft, a flanged housing upporting said crank case and provided with an upwardly open annular channel immediately below the bearing end of said crank shaft, said channel being of smaller inside diameter than the diameter of the crank shaft, whereby to extend across the projected bearing surface thereof, and suction means connecting the channel with the crank case interior for the transfer of oil from the channel to the crank case during operation of the engine.

'7. In a two cycle internal combustion engine having plural cylinders, a piston operating ineach, an upright crank shaft, means operatively connecting the respective pistons with the crank shaft, and a crank case provided with separate compartments each opening into a cylinder and with upper and lower bearings for the crank shaft, said crank shaft having an annular margin at the lower end of the lower bearing, a fuel and oil supply passage leading into the crank case, rotary valve means connected with the crank shaft and adapted to control communication be tween the respective crank case compartments and said passage to maintain said passage substantially continuously subject to crank case suction, said pistons operating oppositely in the respective cylinders, a flanged housing supporting the crank case and provided with an upwardly open annular channel immediately beneath the lower crank case bearing and beneath the said margin of the crank shaft, said channel having an inner diameter smaller than the diameter of the crank shaft margin, and duct means leading from said channel to said passage for returning to the, respective crank case compartments oil tending to seep along th crank shaft through the lower crank case bearing.

WARREN C. CONOVER. CLARENCE L. JOHNSON.' 

